Omnidirectional range



Allg 31, 1943- D. G. c. LucK 2,328,476

OMNIDIRECTIONAL RANGE Filed oct. 29, 1940 :s sheets-sheen 1 F j Aug. 31, 1943.

D. G. C. LUCK OMNIDIRECTIONAL RANG Filed OC.. 29, 1940 PI/'E SELEC'MB T KEYEB 3 Sheets-Sheet 2 31, 1943. D. G. C.

LUCK 2,328,476

OMNIDIRECTIONAL RANGE Filed Oct.

29, 1940 3 sheets-sheet s NL \I" :poration ofiDelaware This invention relates to oinnidirectionl radio ranges of the type described andy claimed inPatent- Dio. 2,208,876 Whichaissued to D. G.`C. Luck,

l -Brieflmthesystemtowhich the pre.sent-11151,'eri-v. j

tionLrelateS eirivolvesle reelle. beacon: inlwhiehie rotating. direetlveeld pro'vdedvwith ieferenee merk. determines; the beerine ,pfv @receiver respect to 'the beacon.'l AV receiver suitable for use with a radio range ofl tliistyp'ejis ,alsdde-rscribedin .the-aforementionedpatent.- Tnefrot'at-r ing; IdiO-beacon is obtained by lcqmbiningethe uniform-.radiation -eld 0f erA eenirelly leeetedenff tenrlejwith e :pelli 0f fleure-effeight Yelflsvillen.;ff

ducedv-by a, pairof Adcock antennas,l the like,

modulating: voltages Orf-Which arein,rebate-,C111e.fly

yl5 energized by leide. bend frequenemeul 'ri.ts,;'fthev Yingfrf-retardingthejphaseo `the rotating fieldf tioriffis 'correctedgvso' :that 'the phase at"the' amount. `Wh re Lthe' frange i dii-ferent-` 'directionsja outfits -aXi'sfofrtati the-"slightly non-'uniform'- rate v'offrota- Cardinali-peinte Xref: the .eem'peselz iJ-lfvlftlti eerst,"

rature.: In the previousrefreneemenlitlle'modela r latine voltage ities .obtained;direetlrfwmfthe 60Vv cycler powervlinesf The use of the poWei line .tQ

obtainniodulation is not desirable; hoWeyerQsi-nce thesepply line. :frequency le ineenvenietlyfelose;

t ,nerbhiweistiis minimized:

* fTheinveniien W111 lbe t ,o

`theifilowing*descriptiowwhen consideredinfco totheypropeller-blade frequency vo f mostairrait,

and=isfinrst1iciently constant, kIt is* theref IVeai'ir obieeeefthis invention te provide e, fseuee.- 0f.

modulation frequency fora radio -rangeewhichoiis f independent, of changes o in amplitude fendi 'ffel ieeleeeterizedby hlelieteblllllb; .1 i ey above mentioned "patenia system Ifor checkingthecalibration of a' receiver is-described which, comprises radiating four {equally- 'Spaeel eellbretine @pulses 'Corresponding f te," the fellr quad-rant directions north, east, ysouth and West;` of the rotating-field.` These calibrating lpulses, must'be' accurately timedrandmust bear afdeflf'f queli O lthe commercial j power line, vand which' nite lrelatjml; to the keying impulseY :means lof l ie the feperetlenief this, iriventie Whicl 1the :reference.marllrfreferred tola'lyelis radiated. therefore a' further lob'ject-o thisinvention to provide a sourceoffv'oltageforj anY omnidirectional range which includes a plu-jrality of accurately timed lreference pulses""for calibration, one of whicl'ifs utilized during'norintervalsto produce a reference, mark.

. ItfWill; be appreciated that ifthe tmingofgth'e i reference jmark is to correspond'v With the exact f, i instant' 'thatv the'krotating radio eld pointswduel north', for' example;k that `Aad-jlistrneiits :must/be providedto control the modulation circitssdjas f i tosuitablygadjust'the .phase of the modulating" i I voltage to produce ,this` relation; In add i.tircinlz` slight discrepancies in .therelative amplitudes-of mentof the 'directional antennashjas-'Wella ldis- ,y Y

' al operationto key the radiated: fields at flied;

ingvoltagesfirifaccordarce with thisini/enticin;"j` 'I legilsf'correct, and, in e fioucjiritercardinal jeeuthwes 11.@- '7 eeefineeftoed mi* neetienl vwith.v` the; @Geom-peering? `elleilirles.tm which "figure: 'I isjfaschematicvcjdiagramf-of Zani; omnidirectionaliangeand ae'sourcej of Aliriodulat- ,lleure2v is, afeireuitl diagram 0f e Pulseeleeer* diagram 'of a reinersilcile` phasefadjkuste eastwestairiterinai239; Gutput from the rmer l balanced modulators 23 and 25 supply radio fre-V quency currents modulated at a convenient frequency, say 100 cycles, which may be termed side band currents, to the bidirectional antennas 21 and 29, respectively. The modulating voltages for the balanced "modulators are obtained from the modulationsource which Will be subsequently described in detailfor the presentitl being in phase quadrature. a rents in the two antennas ofl each pair willbe in phase opposition, and the modulated carrier frequency currents in the north antenna, for example, will be in phase with theVV modulated carrier frequency currents inv theeast antenna.

The carrier frequency currents in the central or omnidirectional antennaSl are adjusted to be in quadrature phasewithfthe modulated carrier frequency currents .in the four directional antermas.V As a result, the elds.. established bythe vcurrentsfin the-bidirectional antennas are eachofthe conventional figure-olf-,eight type, the am-` plitudesof these fields ,varying in accordance with. the modulating voltages'tofproduce 'a resultant iigure-ofY-eigh't field which rotates aboutthe com-vA mon center of the four antennas at the frequency field'so that; the'cardioidfminimum fis not re-l duced to zero. Thecardioidfield rotates about` the central antenna.v at the frequency of the modulatingyoltage. Figures 7 to `1i) illustrataone cycle. ofrotation ofthe cardioideld, `the i'leld ci y the timing mark or impulse by 270, and in a receiver located due north of the antenna the field will be in phase with the timing impulse.

These phase relations are illustrated in Fig. 11 to which reference is `now made. Eight sine Wavecurves N, NE, E, SE, S, SW, Wand NW are shown plotted against atime axis correspondingto one complete revolution ofthe rotating field; The N curvefcorresponds to the' north- Ward Vradiationlof the antenna, or the corresusicientto understand that the modulating volti .Spending voltage "Produced in e receiver due ages applied to the two balanced modulators are f The radio frequency curnorth ofthe antenna. It will be observed that the maximumof this voltage would occur at the f time TN, at whichinstant, however, the eld is g momentarily reduced to zero to produce the reference niark. VVThe remaining curves correspond similarly tothe fields in the other directions, and have their maximums spaced apart 45 so that theyoccur at successive time intervals TNE, TE, fIfSE, etc. i

-" "The, maar@ f Referring again to Fig; `l, the modulatorforv providingaccurately spaced timing `and calibrating impulses 'andmodulating voltages ofcontrol-` o labio phase and amplitude is illustrated in block kdiag'rauf-'form inthe! lower portion of the iigure.

While'the elements which constitute the circuit arrangement villustrated may takemany forms, some of whichI are'well-fknowm'it-is to be underlstood-"that` the' "invention is` not limited i by kthe particular circuits of-"the devices which have been illustrated merely to provideiullqinformation concerning the operation of Athis device.'

The pulse generator v3,9; the circuit diagram of` .which is shown in Fig. 2"is a device for producing'a succession f short impulses of the type illustratedvinV the small diagram immediately being shown at successive times, a quarter. cycle apart, 'IN, TS and 'IA W, as the maximum held passes through the MiourY cardinal'A points of vthe compass. I

By'arrang'ing the keying` or referencefimpulse produced bythe keyerfifl Vso that the antennas are deenergizedjatffthe instant the maximum of the rotating cardioid is d uefnorth, for example,

a constant reference mark?` or impulse is estab-.v

lished by'means' of whichtlie'phase of the rotating ield taken at any point abouty thecenter of` the field may be determinedwith respect to the reference or keying mark. Thus, a receiver: lo#

cated due east of the antenna, forexample, will receive a signal the modulation of which vWill vvary substantially sinusoidally as the field oro# velope sine wave willoccurSO?, that is, a quarterV of a cycle, Vafter the Varriyal of thetirning mark, l assuming rotaticngima clockwise` direction. Forl a receiver locateddue south of theantenna the phase Vof, the ma:iirnum;` ofi the voltagel produced by the rotating eldywillfollow the timing mark by 180. Similarly,gin areceivervdue-Westror the antenna the phase of the rotating field will lag above the pulsev generator inFig. 1."`Thefre quency of the` output of the pulse generatorlis preferably'eight.times the frequency of modulation, and'inthe'present case is800 impulses per second, since the assumed modulation frequency is 100 cycles per second. By rmeans of a switch 4| theoutput of the. pulsegenerator 39 may be applied directly tothe keyer 31 tomodulate the" radiated field `eight times per cycle if desired.

'I'he'pulse generator, output lis `also connected to` the input circuitsof a pair-,of pulsefselectors 43 and A@ i 1-he output circuits of the pulse selectors areiiapplied to; and' control the operationk of a Square wave generator 41. Output fromlthe first pulse selecto-p43 isalso `applied to the Akeyer 31 through the fone pulseper cycle contact of the switcha4l; A control voltage derived from` the output of theyoltagev supply system, or `directly `from the fllteredoutput ofthe square wave gene`r ator,"is also appliedlby Aalead 5U 'to the two .pulse selectors. Since the `elements so foar described may notbe known generally, theyjhave been illustrated in detail in Figures 2 and 3` and Will bedescribed hereinafter.' Y

The output 'of the square'wave generator 41 is applied to three channels. The iirst` channel includes a 90 phase shifter dafnorthsouth phase control 5l, anamplitude control 5 3,"a differential amplitude' control '55,` and .ai tuned ampliiier .51,

includes'an' east-weist phase control 59.2.11" amplitime contrai s s, .the diiiereritiai amplitude con- .Y trol 55, and a tuned amplifier. G3i The third chan.-

nel .includes a .phase .shifter 65, a .phase control G1, lan amplitude control 60, andtunfedfamplifier" 1i lThe output .ofthe tuned amplifier` 51 in the iirst channelis connected to 'the run terample.

north-southlcalanced-rriodulater'23jr 'The outputf of the'tuned'amplier-FSBin thesecond channel 'is 'connected to Vthev run `terminal l of Y another section T of the run-calibrate switchfby'mean'sfof which this voltage is vapplied A to the'eastwest balanced modulator 2'5. 'The.outputcfthetuned Y after the phase shifting-anarcontror networksas amplifier 'H in the thirdcl'rannel':isfccnnectedtoy the calibrate terminal of -sti-ll another section; 'l'

modulating the omnidirectional antenna I3 I fThe output ofthe tuned anjrplifier 51 inthe i-rstchane nel also connected `t'o-'Tthetwopulseselectors. 43 and 45. This same output is also -ce'lnn'ectedfy to -an east-west'reversible adjuster 15, lthe output of which `is fed into 'ayinixerf Blij Theoutpllt of thel tuned amplier' 63 is# also connectedtott the input of a north-south reversible adjusterl'l, the

lo ofthe run-calibrate switch through Which'fth-s l voltagemay be applie`dto'the modulator 35mfor'l shiftingfarrangement "may be utilized,fa preferred l t 1 circuit isfshown i, in Fig. 4. By,` utilizing;varialcxleVV output of which is also connected to the mixer 8l The output of 'the ihiiierj v8| is connected to rthe run Vterminalof A'the run-calibrate switch 1T. Energysalso fed-into themiXer-.Slfroma i rejector 89 may be included in the latter connection to eliminate speechfrequencies which are-- near the modulation frequency,y 100 cycles, pro- Operation of the modulator The operation'iof the'modulation "voltag'efsup-l ply/system Will now be explained.' `vAs indicated.

. thefdifferentiaramplitude:contro1 .Sa'f'thepurpose ingi'oppositelythe amplitudesfof the voltages in above, the pulse generatori!) supplies-a succesf' sion 'of short pulsescfvenergy tothe two' pulse*` selectors 43 and 45. v-As'"shoWn'-irrFig'. 3;tlie input circuits of. these fpulse selectors -contain Vbiased `rectifiers -Sl and'93, respectively,and are also tubes are normally nonconducting.' The bias is substantially equal? tof or slightly greater than the f peak-ofthesine Wave voltage derived from ami phase control'lis illustratedinligvsglgto'itvhiclfiy reference is lno'wzenade. f It! will: be obsehved, that plier 51 V-which is appliedtothe rectiersf vThe control-'i sine wave voltage is applied-in phase opposition to thetwopulse selectors as'v indicated by"`the-smalll curves of Fi'g.-f1-^immediate1y above and below'these elements. As a resultethe,{cnilse`` selectors are'able to pass onlyfoneiimpulseiout" of each group o f eight `generated impulses.- the se pulseselector will-pass pulse'liofSduring.ther

alternate half cycle. `'Ifile tvvo selectediimpulses which occur during alternate half cycles of ythe mduifatine frequency; areappliedftotheinput circuitof a'square Wave 'generatord'Lthe details of-which are -also shown in Fig: The square wave'generator comprises a pai' offtul'es""9 5 an'dr;- 91 connected iria Well-known'multivibratorfc cuit, in which the alternation or cend u-etivity''be-I tion ofthel impulses frornthefpulse selectors. L

a result the square Wave-generatorproducesja l square Wave output voltageWhosefrequencycor- L1 wave' ygenerator bythe sergente impuise'susninn more accuratel in phase thanjfthat Whchfwculd be' obtained by driving'-a-sinel'wave,'oscillator or ex? The Y square-wave voltage 'is' preferably- .this.provides.automaticsynchronisatie at-,the

^ Whhlprovides a.l furtheradjustment ofthe phg e Aknown potentiometerliarrangement in which the ff" l the phas'esof the,gure-f-eight-V eldfproducedby vReferringto Fig.6, Vvi/hiohfis a' space diagrarnofk f doesinot'radiate ina'northlsouth direction. Con- ,1.

adjustment-br'thefncrtnesouth phaseccntrel-5|j p converting thejoutput ofxthleY squarewave gene erator -to'zaI sine'wave mayjb'e'includedsbeforeo resired. Extremelyistableoperationis 'obtained by usingthesine wavevrepresenting the fun'cla-y n mentalcompohent oftheYsquareiwaveoutputzgoi f "il the-'generator 41 to' select everyifcurthimpulse 'j for controlling the squareA wave ,generatorg'since properrequency. A

The purpose'of-the ,90f pha'seshifter H9' Yis to f. provide the'necessaryphase.quadrature..relation between" fthe: 'modulating voltage'` for Vfthe 'northantenna' system.v While .anyconventional pl'xasev 5 resistors 'in thiscircuit acoarse adjustment-,nf .th-e; phase maybe' had, which isi-'followed by/alsecond l. 'Y adjusterterrned the north-south phasecontrol-'r The amplitude-control device 53 cornpufises:avvel'l'-.xl

amplitude -oifthe yvoltage .inthe-first channelfrria .l be controlled; Theipotentiometer'fisxfcoupileclsto j, i

of which is toproV-ide unicontrol meansfdr Varye:

thislphas control device. variesthe :phase-of @the voltagewhichmodulatestheenergy.radiatedhyfi i the :northasoutlrantenn'a system. C'onsequently,j

the'lnorth-.s'outh antenna; with-respect to; ftheitim-j ing impulse, maybevaried one Waylorthelother." f

sequently;v shifting`the phase of the ilor'th-muthfw, .l flgure-of-feighteld'Willghave' no eect`fo1if-the-- l Y resultant-ra"diatic'my Vin east-West- Edir ct n l otherwise stated; and as illustratedinstala; the

man@ south @Meer given;time.;.lievi/'evenv I north '.andg'south phases, y varies met atrial.difference;` L (oq-a) (1s-caw@ remainsxcon'stant. The'j'fectof'theeastfwestphas vlcon simil the orth-soutlrphasecontr st -vfst anten' and south positions'is, normal, asinfFig. 11,101,115j the phase of theiresulta-nt or ca'rdioidK field' in the east andwest directions,.curvesEi.andW', has

been shifteduby the, angle fy. ,A sgbefore the,sum

ofthe east and Westphases isi/aried, but their difference.remains.. constant. i 1 Y a The phase` shift thusfproducedy inthe modulation of the radiatedeldis equivalent to making the .rate of rotation of the cardioid non-uniform throughout each revolution;` Y The pliase-of the field in-tliefnorth-,southA directionymay be` adjusted; independently of` the Vphase in east- West direction, ,andV vice versa. .The purposeofj these adjustments is not to produce-thenon-uniforrnityl of rotationY or 'errors a and 'y as indicated by Figs. ,12.and 14) asa desirable end, but to at,`

tain' the "uniform rotation characterizedrby the relations of Fig. ll,notwithstanding `disssym.-

metries, ofthe type referred to above; which Y:pro- ,y

duce errors inthe directionalgradiation. If the system may be adjusted .in the various quadrantsto produce` slight errors, itfollcJWs` that the same system may be used in the same manner to correct preexisting errors which can not otherwiseVY be overcome.

An important feature of the present invention is the provision for advancingthe.phasegofgtneV radiation in thefnorth direction, forexample,

and retarding the phaseof the radiation in (the, south direction.A That is, forvarying thedifler` ence of the phases inopposite dir etions,I keeping their sum constant'.` As 'pointed' out above,

the phase .control devices described immediately above advance or retard the north 1and south,

phases in like manner. YI havefoundrhowever, that the phase of radiation inv opposite directions Y 2,32a47e phase, of tha resultant isshifted in a given direction While the phase'in the southdirectionis shifted in Atheopposite. direction.V This is', illus;

trated injls'ig, v12in whichtheieast-West curves,

south ,modulation `andffor similar reasonsgshifts thephasegotthe resultant radiation oppositely by theiangles 90| andZTOK- in theeastland;

westdirections butr does not affect the phase, in

thevnorth-south directions;4 This` is illustrated may be varied oppositely by applying vtomthe j omnidirectional radiations.. controllable amount of4 themodulation voltage derived from` the input to the balanced modulators. Thusp in Fig; "1,1 the reversible adjusters 19 andi-83 select a por-` apply them n controllable-.phase to a'mixer` 8i'. Thedetails of these elements are shown in Fig. 5 to Whichreference is now made. f:

1 Thereversible'adjusters 'PS and'lSB aremer'elv* potentiometers .having their ,ends` cross-zone` Vnected 'so thata 2continuous'adjustmenft may be had -between oppositely phased modes of` connection.` i When positioned in the'middleof` rthepotentiometers no output voltageis available, While movement in onedirection `produces aavoltage of one phaseand movement inthe other direc#`V tion, producesal voltage of theV opposite.l phase. These voltages Yare applied to the omnidirectional radiation modulatorl through a'mixerl.. which may include,r for example,r a small `common impedance Ze fed through largemlmpedancesmz from thevadjusfters lil and 83, andf connected in series `with the split secondary of 'a'.transformer 99,"thefprimary` of which-` is conneoted'to the speech amplifier 87; These impedanees may :be adjusted innphase angle to lcompen phase shift in the modulator'35.V v

Operating the'fnorth-fsouth `reversibl djuster 83` causes a modulating voltage to'lbefapplied'to the omnidirectional radiation, the phase of which ircuitV sate fortuitousf tion of the quadrature modulating voltages;andA

directions.

.Brv manipulating-both thephasecontrolada-.1` vices `and thereversible adjusters ,i;itis therefore possible-` to control ,independently the phase t of rradiation in the Vfourcardinal'.directions, north' southeast and West. Anyerrors inherentmn` the antenna system Vor its surroundings; which pro` duce errors in these directions can, therefore, Abe corrected, I r

Y Adjustment fof* radiation in intercardinal #directionsV Y The circuitso, far described makes possible the control and adjustment vof the phaseoithe" modulation ofthe el-d radiated inthe four cardinal In addition to" thisyit is ,necessary tor providemeans for assuring correct modulation phaseI in the intercardinal directions. This is the purpose oflthe Vdiierential4 amplitude control Whena receiverjis northeast ortheantennaAV theeld intensity normally reaches a:maxiirunn- 45 `after `the -referencerimpulse ,In thelvsouth east, ,southwestv and-northwest positions the phases volfthe iields arelvrespec'tively 135?, and 31N/ after the timingfimpulse. y i

, Referring to` Fig.-` 18the `two gure-of -eight rau diation patterns'NfS and are shownhavf ing differentA maximum amplitudes. ASince the fields actually reach maximum at, diierentitime,

Y intervals, by reason of the quadrature phase relationjof, theV modulating voltages,4 the` maximum amplitude'illustrated for the east-west'iigure-ofeightmust-.be understood `to occur 9,0? after ,that` for the northwest gure-of-eight pattern. When the differential amplitude :control is` set` so that the amplitude ofthe-modulating Voltage ap.-

pled Ato thegnorth-south antenna exceeds thatA of the modulating voltage applied tothe east- West antenna-the .amplitude .ofthe resultant field att;hegintercardinal pointsnortheast and southwest reaches-a maximum before andlafter,`

respectivelmthe time at which `maximum would 'bereachedI-inthe normal casev'where theram- .f northeast direction', curve-NE', is shifted inthe corresponds to'that applied tolthe east-WestV anthe east-West direction can b e a slight ,change in the amplitude Yof the resultant modulation, but no @hnge in tS phasea'nslei .In the northfdirection,

however;` aquadrature relation existsv andthe same: sensel asthe phase Vof the welkziirrtlie` southwest kimgetion,curve lsvv',what ,the phaseff theeldin the soi'ithea'st-direction,l curve and in the riorthvres't'direction, Curve'NW, are likewise-.shifted in similar Adirectio'nsby thisladlvju'simentll'Corsequetiy, itis possible" by Liafrpl. uiatmg'fne different" amplitud? control'detice r'eiic l weerslag eiiorn th fvr linti insure correct operation,

overcoming preexistingerrors dueto inequalities; in-the mechanical andelectrical systemi f ,ff'Aizgfiilgtinent forreceioerfcaliorotion Y The'purpose ofthe Calibrating switches, Y which may be connected on a single control shaft, if f Y c eiver. in phase, respectivelyyrepresent the effect of,

p cardinal: directions, or to make any given inter-, i

`cardinal direction correct, thusmal;ing` p9ssible a more accurate phasing g of thej rotating field.

vItis to be understood, as before, that the purpose of this adjustmentismot-to create errors but to desired," is to remove the bidirectionalelds and to modulate the omnidirectionalffleld rvvith'a sine .v waveY modulating voltage, phased' so that'the maximum field'"inten'r'slityl foccurs ,atftiIne'TN This. switch? may 'fbe j i" n'anuallyY operated jupon request. to permit the .pilotfof 'an airplane; to ch'eck'his receiver, orv may be operated automati cally at statedintervals as desired. "In addition, switch' lll maybe operated to modulate the field vwith eight -pulses per revolution. The eight f even to the extent of 2th intensities ofsaid-fleldsingacccr ,voltages Whichare in's'ubst'antial phasej duadra-r -turerelatont produce `Y tages to lcontrol-the rate'jor angula said resultant field.

pulses correspondto` the four cardinal points of v the compass, north, "south, east vturd west, and

also the four intercardinal "points northeast,

. southeast, southwest'and northwest. The cali v bration yis r independent of the position of the aircraft with respect'to'tlie transmitter. Regard# lessor the Yaircraft position, the V pilotl `vreceives' a series of timing impulsesanda modulated field Corresponding to that which `would'loefreceivedif he were, due north Yofthe transmitter in norfmal operation. It willbe understood that Y'durir'ig the above calibration no rotatingcardioid is produced since the modulating voltages have been removed from the balanced modulators; The

phasegshifter 65 provides an initial phase shift` to compensate forthat of the 90 shifter 49'and the phase shift inherent inthe modulator 35 and the phase control V(il provides an operating adjustment whereby the phase ofthe modulation' of the vomnidirectional eld may 'be Yadjustedfto the proper value vWithl respect to the timing `1I n,

- pulses. This relation is shown iny Fig.l 16 Where the single sine Wave curve A rhas itsmaximum at the time corresponding to due north, the single' curve indicating that the phase of the" received' is independent of the iposition vofthe-Srevoltage `Curves B and C, retarded land advanced adjusting the phase control 61.

The omnidirectlonal range herein" disclosed thus involves a unique source of modulating voltrotation .of saidr directional Aradi v`di-r'ectional fleldsl anfing thearnlliude,-1-.0f;theV

energy producing aid directional iields t andadiustinetne relativeamrlitufd f4: -fafradio range: :harinelmeeos fof rrO-F v ducing g an` omnidirectional radio .frequency field j and a-pair,013%directional.fields,4 and meansf for causingzthe amplitudesof said vdirecti nal":fields to be varied; at a predeterminedfrequency'forff ,producing al resultant,,directionalV i'ield rotating at? Saidversiin;frequencrothe meteo@ ai Org# ation whichincludes the steps of derivingavarying voltage, 'utilizing saidv voltagefto 4. vary Athe amplitude of the energy producing said f eld to 'vary'the intensityoffsaid omnidirectional iield, and, adjusting the ,amplitudev and :phase off said v varying voltage to 'controllthe 'angular rotationofsaidiresultant fleld.f

5;*111-,a1adio'range'having means for produc-- ing an omnidirectional liield andgafpair of ydirec-A `tional fields and for 35? theinten'sty ofjfsaid fields at a/ given and'inrelativefphasequadratureiii/hereby.a. ro.,y .tating directionalresultantffieldis-produced, .the

varyingthe amplitude ofthe energy producing-jsaid'- directional fields tovary method' of operation which includes thesteps of ing in `phase tothearespectivervariations .of said 1 age which includes means for correcting for 1 er-rorsinthe phaseof the rotating fieldatthe AVfour cardinal points' of thecompass and the in- "te'rcardinal points as Well. A v

I claim asm'y invention:

1,'The` method of establishing a `radio range which includes the steps of producing an omni- -jdirectionairadiofrequency field anda pair of di'- j rectionaliields, 'varying the ar'n'plitude ofthe i energygproducing said ldirectional fieldsto Varyl the intensities of said fields in accordancewith" g5 plitudeand phase iofflfsadrombned -ltae ft@ 1 f jtherebyadjusttnepnasing ofsaidrotatng fieldy voltages vvWhich are in substantial phasehquadrature relation," combining 'said-iieldsv toi produce a resultant directional iieldvvhch 'rotates'fat the frequency 2. The-,method of establishing a 'radio-v range`v interrupting Y atleast reference impulses, derivingfvoltages corr'e' s r 1f nd-, v

l directionall fields, 'combining1-,- said derived .jvol-v aid yderived ifolieges respect to said referenceirnpulses,v N V6.'1In a radio :range :having-means for roducin g an omnidirectional field and 'a pair-gd .directionalelds and-g for va'ryir 1 gthe,amplitude` of thev energy producing said directr alelds at agiven freque`nc-y: andpzrelative phase quadrature'-Y so thatjarotatin'g directional resultant eld is pro-.f duced, the-methodjoioperation `which 1 includes ,i the steps fof-,interrupting at least one of saidffields of said voltages, and adjusting the relay .tive phases of said voltages tocontrol the angular rotation of said resultant field.

j@ radio range having establish,timed-A reference impulses, deriving yolf tages"'corresponding(respectively to the variae H tions'of the'intensitesliof;saiddirectional fields; i

' combiningsaid'fderived voltages, utili 'n g sai'd y modulate the amplitude of field, aridfadiustnsthe am-Y f combined Vvoltages to said omnidirectional ith respect t'ogsaidI reference imp'ulsefs' Ina? combinatior 1frl means rectional radiation the instant said field reaches'a maximum 'in given direction lto establish reference impulses,

niheintensiuesof saiijfnelds maccprdaneeivinn one 'of-saidfeldsonceper f 1 revolution lof said fresultantjneld to establish combnedvoltges 'bovary s the amplitude'of said omn-idirectional .iie ld, and

-adjusting-the;amplitudes of to adjust the yphasing of vsaid .resultant yfield ,iWith wom-ane fomnidreiinal for producing? 'a'dif` ield rotating atapredeter- (mined`r frequency, means for keying said field at rectional radi-ation field rotating at dio range -having means'ior producinga', lidi- `minedl variation frequencin means'ff kin a 'given ,direction `-to establish reference -irn- Ap reiieierfa', 328,476 i 'rotating at a predetermined frequency',` meansifor producing an'in'stantaneous change in:y the' amvplitude of saidresultant `iield once for each revo- /lution o'f said eldto produeea'reference impulse 5V whereby-the azimuth of arecever with respectito f said-antennas may be determined by ycomparing the phase of said AVrotatingiiie'ldtofsaidlreierence impulse, means v"for selectablyi'ldeenergizing "said directional antennas and i for varying the power pulses, means Vffor inde'rendently adjusting'Itlie'iV lo input to said omnidirectional antenna `at said lfre- -phase, with jrespect to said impulses? o'f fthe 5in# uireetion at :right angles to said -igiveii eireetion, and Ineansffor-independen-tly adjusting -tlie phase of the;intensityY `vari'ation -f -said ifieldiinfd'irectionsintermedia'te saidgivenfdirectionjandfsaid t seorlddiretoni Y f i 9.In rcombinationwithI-afradio-"range "having "meansfor producing Aan uonnnidirectional 'eld of jwliichjconibine *toiproduee 'ai resultant directional field ,Whose axisr ofniaximunrradiationl rotates;v at 'sai'd` inoduiationfrequencymeansCfonkeying one of `rsaid 'fields atiitneg'ijhstaiit *saaie l axis peineides with ya given azimuth '3 to establish reference? imomnidirectional 'eld to" be with the variations of saidfbidire nonnina-es;

intensities of means foifproducingadirectionaliradiatibnfield'i 'rotatingin "horizontal-plan t-a predetermined frequency; nieans forslkeying said'fleldfoncsper v revolutionv to -establi'sh Preference impulses;the

lliiase'of theradiationf `1"iel`d inanydirectionbeing e 'quency, and lmeansyfor "adjusting the relative .pliasejoftsaid 'omnidirreetionalnjiield1and said 'referencefinipulsei t wtf; "y

' .13.`In a radio transmitter jhavngjmeansfior 115 =`producing an omnidirectional ,radiation field-and apair Vci? directional fields which combine to [produce V4a resultantfleld, thepcoinbination of `means fonderiving tvvo` voltages y which arejinrelative Iphase quadrature, .mean's, ,for "utilizing 'isaid l:de-

lzoi, rived voltages vto produce variations fin "the ambplitudes 'of said directionalields, respectively,

andmeans foncontrollinglthe'angular,rotation of saidresultant eldbyadjusting the amplitudes of said derived voltages. 5 i

4525 4.77111 airadio'transmitter having rneansforA fproducingian .omnidirectional radiation field and a pairof Y` directicna ,1fields Ywhich combine to 4kproducea resultantfiield, rthe combinationtf means forV causing the amplitudes '.of `said idirectional fav-30`f`1elcls to be varied cyclically andiiurelativephase quadraturefto `produceA ar-:sultant field which --rotatesfat `said cyclic frequency, andlrneans for controlling theiangular rotation offsaid resultant -i'ield by` controlling-the de'gree of. .amplitude `35 variation of ,said directional elds. i t

' 15. In a 'radio' transmitterhaving ymeansviior producing :an omnidirectional,radiationfeld and i a pairv of directional:iieldsfwhicheombineto ,produce a-resultant-,elithe combination oimeans maximum that? direction with rrespect-itojithe ."tiirieoA saidreference impulselmeansfor :adjusting thie-sux'nJ of 1"the phases f of th'e1 radiation' `iield A:fields l to-ibe yvaried cyclicallyfandsubstantially yin relative` phase *quadratureto` producea-iresultant ,ii-leid which rotates Yat said-,cvclicA frequency, f and :means :for controlling i the `angular rotation i of 'asdjustig fof :fthe k phases .,Of them Said resultant byicontrouingtlle ,Said vrelaradiation 'fjldjrneasuredirr oppositedirections'. 11. combination, L'a `pair of idirectional antennas and -an l omnidirectionallantenna,rneans a reference:firr'ipl'ils'ewhereby"tlie*a.'zi1inutlfirofl-am g W' varied cyclically in phase quadrature? to; produce receiver y-vvith respect -tos'aid :a `temi-as may :be determined by Veormiarir'ig f thefpliasefof' said r ro- "tatin'gfeld and saidreference` impuls'eajand Calif bratin'g #means "for -isrelectablyiiieenergizing esaid input'jto said i ornnidire'ctionaliI `'antenna i so vthat ine ipiiasfe of th omnidireticnai nerd with ie- Aspectft-said rference impulse isvconstant in-a11 'directions- Y irectionaleld mbinationwalpair of idirection'al an-f 'o'f i directional j-itive phase 'z relationH and the, degree of amplitude y variation ofsaid directional'ields.,`

:16.- `In 'combination with `a radio -transmitter having means for producing-an omnidirectional radiation nele and@ 4pair-0f aireciienai-nelds Avvhich--combineto'produce a'resultant field, means for deriving voltages -of `A,a predetermined ire# quency,^meansifor utilizingrsaidfvoltages to -cause the amplitudes of said directional fields to be a rotating directionalfiield,` means foradljusting the amplitudes and fphasesof saididerived-.volyi :tagesymeans for vinterrupting atgfleast one of =said n elds once: per` revolution tof saidrotatingd'irecl 'tional' field f to;` establish reference iirnpulses,` and meansffor 'causing -the amplitude fof said` omni- 1 directionali'iield.,` to bei varied in laccordance `with s'ai'drderived--volteiies` to` thereby; establish the de- `Tsi-red phase betweenf the; rotating dield r-andvisaid :reference impulsesat` 90- degree' interval in-eaclfi `revolution-ofsaidiieldgg ,v j i :fDA-VIDG.-`C.LUCK. 

